Bake-stable creamy food filling base

ABSTRACT

Lipid-based, creamy food fillings are disclosed that are bake-stable up to a temperature of at least about 125° C. The creamy food fillings are particularly suitable for use in products that require the filling to be added prior to baking. In one aspect, the fillings are a solid-in-liquid dispersion having a dispersed solid phase including a hydrophilic powder and a high-melting lipid, as well as a continuous lipid phase including a low-melting lipid in which the hydrophilic powder and high-melting lipid are dispersed. Preferably, the fillings have a low water activity of about 0.5 or lower and are formed in the absence of additional humectants, thickening agents, or gelling agents.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims benefit of U.S. Provisional Application No.61/153,174, filed Feb. 17, 2009, which is hereby incorporated herein byreference in its entirety.

FIELD

The field relates to a bake-stable and creamy food filling base and, inparticular, to a shelf-stable and bake-stable, lipid-based creamy foodfilling suitable for low moisture foods.

BACKGROUND

Foods with textural contrast, such as crispy baked snacks with a creamyfilling, can be appealing to a broad spectrum of consumers. These dualtexture foods may include a lower water activity (Aw) crispy component,such as a cracker, and a filling component, such as a creamy,shelf-stable filling. The filling component, which may be lipid-based,typically exhibits the desired creamy texture from relatively smallparticles dispersed in a lipid continuous phase. However, suchlipid-based filling components tend to have the shortcoming that thedispersion structure can be thermally destabilized in some instancesleading to oiling-out and loss of creaminess upon heating. It isbelieved that such thermal destabilization may be the result ofaggregation of the small particles leading to lipid separation fromother filling ingredients. Thus, such shortcoming renders manufacture ofthe dual texture snack challenging.

In general, two approaches are commonly used to manufacture such dualtexture snacks. By one approach, the crispy or cracker component, whichis usually obtained from a dough, can be baked prior to applying thefilling. In this case, the filling is not exposed to bakingtemperatures, and the shortcoming discussed above can be minimized oravoided. However, this approach can have limitations in terms ofprocessing and limit product configurations, for example, tosandwich-type products. Another approach is to prepare a filled doughwith the filling component injected therein and then baking the doughand the filling together. This approach is limited by the thermalinstability of the filling component at baking temperatures, such astemperatures of about 110° C. or higher, commonly used for crackers,biscuits, baked chips, or other extruded/baked snacks. When the priorfilling compositions are exposed to such baking temperatures, it cansuffer from product defects such as boiling-out, oiling-out, loss ofsmoothness, and discoloration.

To address the stability problems of the filling component undercommercial baking conditions, prior creamy filling compositions weregenerally formulated as water-based systems containing a hydrophilicliquid or aqueous continuous phase and dispersed oil droplets as anoil-in-water emulsion. The emulsion was then combined with relativelyhigh amounts of water activity (Aw) lowering humectants (such aspolyhydric alcohols like polyols, glycerol, sorbitol or othercarbohydrate-based humectants such as polydextrose and the like),thickeners, and/or gelling agents (such as hydrocolloids, proteins,starches, and the like) to improve emulsion stability at commercialbaking temperatures. See, for example, U.S. Pat. Nos. 4,752,494;5,529,801; 6,863,911; 6,905,719; and 6,905,720. These prior fillings,however, are generally unacceptable from an organoleptic standpointbecause they tend to be syrupy or gummy in texture and undesired as acreamy, savory filling (such as a cheese-flavored filling) due tounwanted sweetness and unpleasant aftertaste from the humectants (suchas bitter aftertaste from glycerol). To achieve bake stability, suchprior compositions tended to compromise desired organoleptic qualitiesdue to these additional ingredients that tended to alter the desiredtaste, texture, and/or overall flavor of the filling and/or otherwisetended to lessen the eating experience expected by the consumer.

One example of a prior cheese-flavored filling is a low Aw, oil-in-wateremulsion composition. In this prior filling, the water or hydrophilicphase is mainly made of glycerol (or other polyhydric alcohols),polydextrose syrup, corn syrup, and mixtures thereof. Such constructionof these emulsion fillers may be generally stable at low temperatures,but under baking conditions the fillers are typically prone to boil-outor bleed-oil as the lipid phase can potentially undergo coalescenceresulting in phase separation or inversion. In addition, the water inthe hydrophilic continuous phase may also escape from the filling atbaking temperatures resulting in blow-out of the dough or unwanted largevoids in the dough envelope. These prior liquid-liquid emulsions alsotend to be interfacially dynamic and their stability can be highlysensitive to shear, processing (e.g., extrusion, etc.), handling, andstorage conditions.

SUMMARY

Lipid-based, creamy food fillings are disclosed that are bake-stable upto a filling temperature of at least about 125° C. and, in some cases,up to about 150° C. The creamy food fillings are particularly suitablefor use in products that require the filling to be added prior tobaking. In one aspect, the fillings are a solid-in-liquid dispersion. Acontinuous liquid phase includes at least one low-melting lipid, and adiscontinuous or dispersed solid phase includes at least one hydrophilicpowder and at least one high-melting lipid dispersed in the continuousliquid phase. The creamy food filling is bake-stable at oventemperatures up to about 250° C. or to filling temperatures up to about125° C. and, in some cases, up to about 150° C. In this regard, thefillings exhibit substantially no filler spreading and substantially nooiling out or oil bleeding upon heating a sample of the filling forabout 10 minutes at about 150° C. and, therefore, can be added toproducts prior to baking and still exhibit a smooth and creamy textureafter being exposed to baking conditions up to about 250° C. Preferably,the fillings have a low water activity (Aw) of about 0.5 or lower andare suitable, among other applications, for low Aw crispy snacks such asa filled cracker and the like.

In another aspect, the creamy food filling has a particle sizedistribution that is effective to render the filling bake stable. By oneapproach, the particle size distribution may include at least about 90volume percent of the particles less than about 30 microns and at leastabout 10 volume percent of the particles less than about 4 microns. Byanother approach, the particle size distribution may include a bi-modalparticle size distribution with both a dust particle portion, which hasa sub-distribution of particles generally less than about 4 microns, anda creamy particle portion, which has a sub-distribution of particlessubstantially greater than 1 micron in size, for example, between about4 microns and about 100 microns.

While not wishing to be limited by theory, it is believed that the dustparticle portion of the particle distribution includes a sufficientamount of sub-micron sized particles, which are believed to havesubstantial amounts of high-melting lipid particles and to be effectiveto substantially coat, substantially surround, and/or substantially forma barrier about the hydrophilic powder particles that helps to renderthe filling bake-stable. Again not wishing to be limited by theory, itis believed that the sub-micron particle barrier or spacer tends todelay, hinder, and/or prevent contact between or with the underlyinghydrophilic powder particle. As a result, the sub-micron particlecoating or barrier may delay or substantially prevent aggregation of thehydrophilic powders, which renders the filling stable against heatand/or moisture exposure over a range of milling, handling, and bakingconditions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of one example of a generic particle size distributionfor bake-stable fillings herein;

FIG. 2 is a graph of another example of a generic particle sizedistribution for bake-stable fillings;

FIG. 3 is a graph of the particle size distribution of Example 2;

FIG. 4 is a chart of milled calcium stearate fractions; and

FIG. 5 is a SEM image of milled calcium stearate.

DETAILED DESCRIPTION

A lipid-based, creamy edible filling is provided that remains stable atcommercial baking temperatures and ambient storage conditions.Preferably, the fillings have a low water activity (Aw) and are suitablefor, among other applications, low Aw snacks. As a result, the creamyfillings of this disclosure can be applied to low Aw cookies, crackers,biscuits, pastries, snacks, and other edible foods prior to baking andstill retain a creamy texture after being exposed to bakingtemperatures. As described more below, the compositions andmicrostructures of the fillings herein have unique thermal andmechanical properties that make them ideal as a low Aw, lipid-based,creamy food composition that are suitable as a filling in low Aw, dualtexture foods that benefit from the filling being applied prior tobaking. As used herein, low Aw generally means about 0.5 or below.

In one aspect, the bake-stable, lipid-based creamy fillings havesubstantially no aqueous phase and are formed from at least onelow-melting lipid, at least one high-melting lipid, and at least onehydrophilic powder that are milled to form particle sizes anddistributions thereof that are effective to form a bake-stable fillingthat remains texturally creamy at practical commercial bakingconditions. By one approach, the fillings herein are stable at oventemperatures up to about 250° C. or a filling temperature (obtained viaoven or microwave for example) up to about 125° C., and in some cases,up to about 150° C. With substantially no aqueous phase, the creamyfillings herein are solid-in-liquid dispersions with a continuous liquidphase that includes the low melting lipid, and a dispersed ordiscontinuous solid phase that includes the hydrophilic powder and thehigh-melting lipid dispersed in the continuous liquid or oil phase.

In another aspect, the creamy fillers herein have less than about 70percent of the hydrophilic powder, at least about 30 percent of thelow-melting lipid, and at least about 0.5 percent of the high-meltinglipid. By one approach, the creamy fillers may include a blend of about30 to about 70 percent hydrophilic powder, about 30 to about 70 percentlow-melting lipid, and about 0.5 to about 8 percent high-melting lipidwith any remainder being optional fillers or food additives, such ascolorants. Percentages used herein are by weight and based on thefilling composition except as otherwise indicated.

In yet another aspect, a majority of the dispersed solid phase is thehydrophilic powder and the high melting lipid having a particle sizedistribution effective to aid in the bake stability of the filling. Byone approach, the majority of the dispersed phase has a particle size ofabout 30 microns or less with a portion thereof having a particle sizeless than about 4 microns and an effective amount of sub-micronparticles to achieve bake stability. By another approach, the creamyfilling has a particle distribution including at least about 90 volumepercent of the particles forming the dispersed phase with about 30microns or less and at least about 10 volume percent of the particlesabout 4 microns or less. This can be expressed alternatively as a D90 ofabout 30 microns or less and a D10 of about 4 microns or less. In yetanother approach, the particle microstructure has a multi-modal or atleast a bi-modal particle distribution.

As mentioned above, the fillers herein preferably have little or noaqueous phase, and therefore, preferably include little to substantiallyno humectants (such as polyhydric alcohols like glycerol or othercarbohydrate-based humectants like polydextrose and the like), gellingagents (such as gelling proteins, hydrocolloids, and the like) and/orthickeners (such as hydrocolloid gums, and the like) that tended toalter the taste and mouthfeel of the prior creamy fillers. Since thecreamy fillings herein are substantially free of water, there is littlefunctional need for humectants, gelling agents, or thickeners. As usedherein, substantially no humectants, gelling agents, and/or thickenersgenerally means the creamy fillers have less than about 5 percent ofsuch additional ingredients, in some cases less than about 2 percent ofsuch ingredients, and in other cases less that about 1 percenthumectants, gelling agents, and/or thickeners. Such amounts aregenerally ineffective to provide any functional benefit for the fillingsdisclosed herein. In yet other instances, the fillers have nohumectants, gelling agents, and/or thickeners.

More particularly, the edible food fillings of the present disclosureare formed by milling the low-melting lipid, the hydrophilic powder, andthe high-melting lipid ingredients at the same time and in certainratios of solid-to-liquid and crystalline-to-amorphous relationships. Ingeneral, blending the ingredients separately or varying the solid,liquid, crystalline, or amorphous relationships produces a non-stable ornon-functional product that either agglomerates the powder during orafter milling or is not bake-stable. Milling the ingredients separatelyfollowed by blending tends to produce less functional or less stableproducts in addition to the added complexity and potential costdisadvantage in production.

Milling the ingredients at the same time not only reduces particle size,but also forms a unique microstructure or particle size distribution ofthe dispersed solid phase that is effective to aid in the bakestability. By one approach, the milling reduces the particle size ofboth the hydrophilic powder(s) and/or the high-melting lipid(s) and atthe same time preferably forms a bi-modal or multi-modal microstructureor particle size distribution having at least two distinctly definedpeaks or portions. As used herein, a bi-modal or multi-modal particlesize distribution refers to a continuous distribution of particle sizediameters that exhibit at least two distinctly defined modes or peaks ofparticle diameters across the distribution. In general, these twoportions of the microstructure include a coarser or creamy particleportion including a distribution of larger particles and a finer or dustparticle portion including a distribution of smaller particles.

By one approach, it is believed that the creamy particle portiongenerally ranges from about 4 microns to about 100 microns (in somecases about 4 to about 30 microns) with an average diameter generallyranging between about 10 to about 30 microns. It is also believed thatthe creamy portion includes mainly the hydrophilic powders. The dustparticle portion is believed to be a blend of the hydrophilic powdersand the high-melting lipids, and generally ranges from about 0.5 micronsto about 4 microns with an average diameter generally from about 1 toabout 2 microns. In another approach, the filler has a ratio of the dustparticle portion to the creamy particle portion of at least about 0.1.As generally shown in FIGS. 1 and 2, exemplary bi-modal or multi-modalmicrostructures of the dispersed phase are provided showing the dustparticle portion as the peak on the left and the creamy particle portionas the peak on the right. Other multi-modal distributions may bepossible depending on the compositions, milling conditions, and otherfactors.

By one approach, the dust particle portion (left distribution) includesmainly milled particles of the hydrophilic powders and/or thehigh-melting lipid and generally includes particles about 4 microns orless and has an effective amount of sub-micron particles of about 1micron or less to aid in bake stability. It is believed that thesub-micron particles substantially include sub-micron sized high-meltinglipid particles. The creamy particle portion (right distribution) ismainly milled hydrophilic powder having a particle size of about 4 toabout 100 microns, and in some cases, about 4 to about 30 microns. It isbelieved that the hydrophilic powder tends to be unstable and prone tosoftening and aggregation at elevated temperatures (especially above itsglass transition temperature), which causes the filling to losecreaminess and induce oiling. It is also believed that this inherentinstability of the hydrophilic powders is overcome through the uniqueblends of multi-modal particle distributions that combine thehydrophilic powders with the high-melting lipids in the particularmicrostructures thereof.

It is believed that the inherent instability of the hydrophilic powdersmay be improved because the milled hydrophilic powder particles in thecreamy portion are segregated by, have a covering about, or have abarrier layer thereabout via at least a portion of the particles fromthe dust particle portion and, in particular, the sub-micron sized andthermally stable high-melting lipid particles from the dust particleportion. While not wishing to be limited by theory, it is believed thatthe coating, barrier, or separation of the hydrophilic powder particlesby the particles in the dust portion hinders, delays, and/or preventsdirect surface contact to the hydrophilic powder, which reduces and,preferably, hinders aggregation of the hydrophilic particles duringprocessing and baking. As a result, it is also believed that thebi-modal or multi-modal particle size distributions enable a creamy andsmooth filler to be formed (with substantially no humectants,thickeners, and/or gelling agents) that does not agglomerate and/oroil-out during milling and upon subsequent handling and baking becausethe coating, barrier, or segregation limits direct contact to theunderlying relatively unstable hydrophilic particle.

Again, not to be limited by theory, it is believed that without the dustparticle portion of the high-melting lipids particles, the hydrophilicparticles in the lipid suspension may tend to aggregate (causing loss ofcreaminess) and squeeze out liquid (i.e., causing oiling-out). Thethickened liquid lipid continuous phase, generally due to the presenceof the dust particle portion of high-melting lipid particles, may alsohelp to inhibit the draining phenomenon, which can also contribute to oraccelerate oiling-out. It is also believed that undesirable boiling-outis often related to the destabilization of the dispersion structure, andoiling-out occurs when the destabilized filler composition becomes fluidor free running during baking. In the present compositions, while notwishing to be limited by theory, it is believed that the thermallystable (high-melting) fine particle structure due to the dust particleportion and sub-micron fraction thereof tends to functions as acapillary network that can immobilize liquids (such as the low-meltinglipid liquids) in much a similar fashion in which a fine sand particlenetwork entraps large quantities of water. Since the lipid based fillingof the present disclosure contains practically no water or aqueousphase, blow-out of the dough sheet or excessive void formation seen inthe prior art emulsion-based fillings with an aqueous phase ispractically not a problem with the fillers herein. For instance,substantially no aqueous phase means the compositions herein preferablycontain less than about 8 percent water and, preferably, less than about4 percent water.

Preferably, the combined mixture of the low-melting lipid, high-meltinglipid, and the hydrophilic powder are milled together for a period oftime sufficient to reduce the particle size to produce a creamymouthfeel and to provide the desired particle size distributions and/orsub-populations of the high-melting lipid in order to effectively formthe covering, barrier, or segregation about the hydrophilic powderparticle for bake stability. By one approach, the combined mixture ismilled for a time sufficient to reduce about 90 volume percent of theparticles to a size less than about 30 microns and, preferably, lessthan about 20 microns as measured by particle size analysis. This canalso be expressed as a D90 value of about 30 microns or less (D90 is aparticle size of the 90th percentile or the particle size at which about90 percent of particles in the sample are smaller than). The bake-stablefilling also preferably includes at least about 10 volume percent,preferably at least about 20 volume percent, and most preferably atleast about 30 volume percent of the dust particle portion with aparticle size less than about 4 microns.

At the same time, the milling also preferably forms the bi-modal ormulti-modal microstructure defining the creamy particle portion havingparticles generally between about 4 and 100 microns (in some cases about4 and 30 microns), and the dust particle portion having particles about4 microns or less. Within the dust particle portion, which is believedto include both the hydrophilic powders and high melting lipid, there isan amount of sub-micron sized, thermally stable particles in a portionor a sub-population including what is believed to mainly be the highmelting lipid particles. As mentioned above, it is the presence ofsufficient amounts of these sub-micron particles that are believed to beeffective to stabilize the filling and, in particular, the hydrophilicpowders thereof, up to at least about 125° C., and in some case, up toabout 150° C. as discussed above.

It has been discovered that the mixture of the low-melting lipid,hydrophilic particle, and high-melting lipid preferably needs to havesufficient quantities of the sub-micron particle portion from thehigh-melting lipid in order to sufficiently coat or form an adequatespacer or barrier covering about each of the hydrophilic particles. Thisis preferably obtained by milling the high- and low-melting lipids andhydrophilic powders at the same time. For example, the combined mixtureis milled for a time sufficient to reduce the particle sizes of thepowder and to also form the bi-modal or multi-modal microstructureincluding dust and creamy particle portions in the desired particlesizes and distributions.

After milling, it is believed that the dust particle portion may includeat least about 0.1 percent, in some cases, up to about 0.5 percent, inother cases, up to about 2.5 percent, and in yet other cases, up toabout 4 percent of sub-micron particles of high-melting lipid that areless than about 1 micron. While not wishing to be limited to theory,such amounts of high-melting lipid are believed to be effective to forma sufficient barrier or coating around the hydrophilic particles torender them bake-stable as discussed above. By one approach, it isbelieved that the milled filler may include between about 50 and about90 percent of the creamy particle portion, between about 10 to about 50percent of the dust particle portion with about 0.1 to about 4 percentof the dust particle portion being the sub-micron fraction of thehigh-melting lipid. It will be appreciated, however, that such amountsmay vary depending on the formulation, initial particle sizes of thecomponents, and other factors. While not wishing to be limited bytheory, it is also believed that if there is not enough of thesub-micron portion of the high-melting lipid present in composition,then the composition may not be sufficiently bake-stable because aninadequate barrier or coating is formed. The presence of thesesub-micron particles is generally shown by the SEM (Scanning ElectronMicroscope) image of FIG. 5, which is discussed more below in theExamples.

As mentioned above, the creamy food fillings of the present disclosuremay also preferably have certain relationships of solid-to-liquid andcrystalline-to-amorphous ratios to generally render the fillingssuitable for co-milling and to aid in rendering them bake-stable. Ingeneral, milling or blending the ingredients separately or varying thesolid, liquid, crystalline, or amorphous relationships produces anon-stable or non-functional product that either agglomerates uponmilling or is not bake-stable.

In particular and by one approach, the fillings preferably have a ratioof total-solid-to-total-liquid (disperse ratio) of about 2.3 or less inorder to be suitable for milling together and to be sufficientlybake-stable. The total solids mainly includes the high melting lipidsand a majority of the hydrophilic powders (minus a certain amount ofnaturally occurring low-melting lipids in some hydrophilic powders, forexample, milk fats in cheese powder). The total solids component mayalso include a ratio of hydrophilic powder to high-melting lipid, whichin some cases may range from about 10 to 1 to about 100 to 1. The totalliquid includes liquid lipids such as the low-melting lipids and anyfats or oils naturally found in the hydrophilic powders. Too high aratio tends to result in excessive viscosity that can render millingdifficult due to pressure build-up and/or excessive temperature riseduring milling. Elevated milling temperatures could further destabilizehydrophilic particles and is detrimental to dispersion stability and thecreaminess of the resulting filling.

In another aspect, the bake-stable fillers have certaincrystalline-to-amorphous ratios of the hydrophilic powders. It wasdetermined that relative crystallinity of the hydrophilic powders mayalso aid the stability both during milling and subsequent baking. Ingeneral, a crystalline-to-amorphous ratio of the hydrophilic powders byweight of the total filling formula is about 0.5 or greater, in somecases, about 1.0 or greater, and in other cases, about 1.5 or greater(such as, for example, when the low-melting and/or high-melting lipidare less than about 55 percent of the filler composition). Since thestability of amorphous substances may be influenced by moisture andtemperature, for purposes herein, any hydrophilic powders having a glasstransition temperature of about 40° C. or lower at about 50 percentrelative humidity (RH) are considered amorphous.

It is believed that too low a crystalline-to-amorphous ratio of thehydrophilic powder (i.e., too much of an amorphous content) candestabilize the filling during both milling and subsequent baking. Ingeneral, crystalline components of the powders include, but are notlimited to, crystalline acids (such as citric acid, malic acid, and thelike), mineral salts (such as sodium chloride, potassium chloride, andthe like), crystalline carbohydrates (such as crystalline lactose,sucrose, starch, cellulose, fibers, and the like), and crystallinenitrogen-containing ingredients (such as crystalline proteins,mono-sodium glutamate, and the like). Amorphous powders include, but arenot limited to, roller or spray dried powders from dairy ingredients(such as non-fat dry milk, cheese, cream, whey, and the like),carbohydrates (such as corn syrup solid, maltodextrin, instant starch,and the like), eggs, soy ingredients, fruits, vegetables, spices, andthe like.

Suitable milling equipment includes high efficiency attrition mills suchas, for example, ball mills, colloid mills, fluid energy mills, pin/diskmills, hammer mills, and the like. By one approach, a high efficiencyattrition mill, such as a Dynomill (Glenmills, Inc., Clifton, N.J.) canbe used to mill the mixture of some or all of the ingredients to formthe dust particle portion, the sub-micron particle portion, and thecreamy particle portion. As explained below, it is preferred that thehydrophilic powder, high-melting lipid, and low-melting lipid are milledtogether as a single mixture. As a result of this co-milling, it isbelieved that a sufficient quantity of the dust particle portioncontaining the sub-micron-sized high-melting lipid particles aregenerated and substantially surround, coat, and/or generally segregateeach hydrophilic powder particle, which thus hinders, delays, and/orprevents direct surface contact and/or aggregation of the hydrophilicparticles. This particle microstructure construction results in alipid-based creamy and smooth filler to be formed that does notagglomerate and/or oil-out during milling and upon subsequent handlingand baking.

The blend of the low-melting lipid, hydrophilic powder, and high-meltinglipid mixture, which is preferably in the form of a coarse initialparticle dispersion, is milled or co-milled at the same time and for atime and at a temperature above the melting point of the low-meltinglipid but generally below the melting point of the high-melting lipid toform the solid-in-liquid dispersion. By one approach, it is generallypreferred that the milling occurs at a temperature of about 10° C. toabout 100° C. and, more preferably, about 40° C. to about 80° C. Themilling occurs for a time sufficient to form the desired particle sizesand particle size distributions described above, which are effective toform a creamy texture of the lipid-based composition and to render theresultant composition bake-stable.

While it is appreciated that a larger quantity of the dust particleportion could be obtained upon increased milling times, it is believedthat the formation of sufficient quantities of the dust particle portionduring the initial stages of milling may be important in forming animmediate and sufficient covering, barrier, and/or segregation about thehydrophilic particles to limit aggregation. Therefore, it is believedthat simply increasing the milling times is not sufficient to form asuitable particle covering, barrier, or segregation because theparticles may already have agglomerated if not enough of the sub-micronhigh-melting lipid is initially present in the mixture. If not enough ofthe sub-micron particles are present early in the milling, theaggregation rate of the hydrophilic powder particles may overwhelm theproduction rate of the dust particle portion and the sub-micronhigh-melting lipid particles therein. It is believed this may beespecially true if a high ratio of hydrophilic powders to low-meltinglipid or to high-melting lipid is involved. Alternatively, part or allof the high-melting lipid could be milled separately and added to therest of the filling composition prior to co-milling to ensure sufficientquantity of the sub-micron dust particle portion of the high-meltinglipid is present in the initial stages of milling and in the finishedmilled product. In addition, there generally is a limitation to theamount of the dust particle portion of the high-melting lipid that canbe included in the filling composition. Too much of the high-meltinglipid in the composition has a tendency to develop an undesirable waxymouthfeel when the filling is consumed. By one approach, suitable levelsof the high-melting lipid to aid in achieving bake stability and exhibitthe desired mouthfeel is about 0.5 to about 8 percent and, in othercases, about 1 to about 5 percent.

As understood by one of ordinary skill, milling tends to result in anincrease of the overall temperature of the mixture even with a coolingsystem on the mill. As the temperature of the mixture approaches andexceeds the glass transition temperature of the hydrophilic powder, thehydrophilic (and particularly the amorphous portions of the hydrophilicpowder) will undesirably undergo phase transition and tend to soften andaggregate, thereby compromising the smoothness and bake-stablecharacteristics of the filler and, in some cases, rendering it difficultto remove the mixture from a blender, mill, extruder, or other mixingapparatus. To counteract these tendencies of the hydrophilic powders atelevated temperatures, the formulations and processing conditions hereinare carefully selected. By one approach, bake stability is obtained byat least one: the desired crystalline-to-amorphous ratios, the desiredsolid-to-liquid ratios, effective quantities of the dust particleportion including the sub-micron particles, and combinations thereof.Operating within one or more combinations of these desired relationshipsenables a low water activity, bake-stable, lipid-based filler to be madewithout substantial amounts of humectants, thickeners, and gellingagents as used in the prior art and without a substantial aqueous phase.

In another aspect, the lipid-based food fillings herein have asubstantial modulus and/or significant yield stress across a wide rangeof temperatures. As generally used herein, substantial or significantmodulus or yield stress refers to a rheological characterization thatgenerally means the filling can stand up or otherwise retain its shapeand will not flow against gravity or a shear stress encountered underbaking condition. By one approach, the food fillings herein have asubstantial or significant modulus of at least about 5 kPa across atemperature range of about 20° C. to about 150° C. and, preferably, asubstantial or significant modulus of at least about 20 kPa across thistemperature range. Further, the food filling has a low Aw of about 0.5or less and, preferably, an Aw of about 0.4 or less, which makes thefilling suitable for a low moisture food product particularly filled andbaked products with creamy fillings and a crisp casing (such as acracker). The low Aw of the food filling further contributes toshelf-stability of the filled and baked food composition. As usedherein, shelf-stable primarily means microbiological stability thatensures the product safety. A shelf-stable food composition or productgenerally means that the composition is safe for consumption undernormal ambient storage, distribution, and consumption conditions. In thecontext of the disclosure herein, it may be obtained by maintaining asufficiently low Aw (i.e., about 0.5 or less). In addition, shelf-stablemay also generally implies that the filling retains a substantiallyconsistent physical, chemical, and quality stability, such as crispnessof crackers, creaminess of the filling, and/or absence of defects (suchas oiling-out and the like).

In an alternative aspect, the lipid-based food fillings herein can alsobe filled and baked in intermediate to high Aw casings and/or doughenvelopes. For purposes herein, an intermediate Aw generally meansbetween about 0.5 and about 0.85, and a high Aw generally means greaterthan about 0.85. With prior fillings, the direct addition of water intothe filling tended to immediately destabilize the filling. With thefillings described herein, it has been discovered that when used inintermediate to high Aw casings and dough, moisture can be absorbed intothe creamy, bake-stable filling through gradual moisture migration andequilibration from the casing or dough. Even with such moisturemigrations, the fillings herein remain stable even after beingequilibrated to a higher Aw, such as above about 0.5. Such unexpectedphysical stability allows the fillings herein to be used in intermediateAw products, high Aw products, and in high humidity environments (suchas up to about 80 percent relative humidity at 25° C.) for extendedshelf life storage (such as, for example, up to at least about sixmonths or longer).

Unlike the prior oil-in-water emulsion-based fillings, the resultantbake-stable food fillings provided in this disclosure generally exhibitthe organoleptic properties of more traditional products (such asnatural cheddar cheese) in flavor, taste, and creamy mouthfeel. Indeed,the edible food fillings herein are generally rapid and clean melting,free from residue, and have a creamy (i.e., smooth, non-sticky,non-syrupy, and non-waxy) appearance and mouthfeel. Additionally, theedible food filling compositions described herein possess a stablecrystalline structure which resists the tendency to bloom or crumbleover its shelf life and provide good stability against thermal abuse. Inparticular, the edible food fillings herein remain stable at elevatedtemperatures without substantial boil-out, oil-bleeding, or loss ofcreaminess.

Using a spread test, the bake stability can be evaluated. As generallyused herein, the filling compositions are considered bake-stable becausethey have substantially no filling spread and substantially nooil-bleeding when about 15 grams of the filling composition in asemi-spherical shape, when applied to a filter paper base (such asWhatman #1 paper or equivalent), is exposed to about 150° C. for about10 minutes. For purposes herein, substantially no filling spread shouldbe less than about 1 cm beyond the outer edge of the original sample ina radial direction, preferably less than about 0.8 cm, and morepreferably less than about 0.5 cm. Also for purposes herein,substantially no oil-bleeding should be less than about 2 cm beyond theouter edge of the original filling a radial direction, preferably lessthan about 1.5 cm, and most preferably less than about 1 cm. This spreadtest is more fully described in the Examples provided herein.

By one approach, suitable high-melting lipids have a melting point of atleast about 70° C. or higher. Preferred high-melting lipids have meltingpoints of about 100° C. or higher. Suitable high-melting lipids includeedible long chain fatty acids, their monoglycerides, diglycerides, andtriglycerides, their alkaline metal salts, and other derivativesthereof. Generally, the edible, high-melting lipids are formed from longchain fatty acids having at least 14 carbon atoms and preferably 18 to26 carbon atoms; preferably, the long chain fatty acids are saturated.Suitable saturated long chain fatty acids used to form the edible, highmelting fats include, for example, myristic acid, palmitic acid, stearicacid, arachidic acid, behenic acid, lignoceric acid, and the like; theirderivatives, including, for example, glycerol monostearate, glyceroldistearate, glycerol tristerate, calcium stearate, magnesium stearate,calcium palmatate, high-melting sucrose polyesters, high-melting fattyalcohols, high-melting waxes, and the like, as well as mixtures thereof.In addition, synthesized or chemically derived oils or oil substitutesmay also be applicable, such as sucrose polyester of fatty acids. Apreferred high-melting lipid is calcium stearate.

The hydrophilic powder suitable for use in the present food filler ispreferably selected from dry flavor powders having primarily crystallinematerials, but may include a mixture of crystalline and amorphouscomponents with a moisture content less than about 8 percent and,preferably, less than about 4 percent. Suitable hydrophilic powdersinclude dry flavoring powders having less than about 4 percent moistureand/or a glass transition temperature of about 25° C. or higher at about50 percent relative humidity. Hydrophilic powders include any ediblepowder that is readily or substantially water-soluble orwater-plasticizable rendering hydrophilic particles to soften, swell,and/or become sticky. By one approach, suitable hydrophilic powdersinclude edible food powders containing at least one percent ofwater-soluble or water-plasticizable substances. Edible water-soluble orwater-plasticizable substances include, but are not limited to,carbohydrate, protein, mineral salts (both organic and inorganic) andtheir complexes or combinations thereof. Edible water-soluble orwater-plasticizable substances may further include edible dry powdersderived from fruits, vegetables, herbs, spices, cereals, nuts, legumes,milks, meats, eggs, seafood, starch, flour, and the like. Examples ofsuitable hydrophilic powders include powders with cheese, fruit,vegetable, spice, sugar, salt, acidulants (citric acid, malic acid, andthe like), flavorants (cream powder, fruit powder, spices, and thelike), tastants (hydrolyzed protein, MSG, and the like), and likeingredients. By one approach, a suitable hydrophilic powder is a cheesepowder, such as CHEEZTANG (Kraft Foods Ingredients, Memphis, Tenn.).

Suitable low-melting lipids generally include hydrogenated ornon-hydrogenated fractionated or non-fractionated oils and their mixturethereof having a melting point of about 40° C. or lower. Suitablelow-melting lipids include natural or partially hydrogenated vegetableor animal oils including, for example, coconut oil, palm kernel oil,rapeseed oil, soybean oil, palm oil, sunflower oil, corn oil, canolaoil, cottonseed oil, peanut oil, cocoa butter, anhydrous milk fat, lard,beef fat, and the like, as well as mixtures thereof including oilsoluble components derived therefrom, such phospholipids. Preferrededible, low-melting oils include coconut oil, palm oil, palm kernel oil,anhydrous milk fat, corn oil, soybean oil, canola oil, and mixturesthereof.

The mixture may also include optional additional ingredients or otherfood additives that may be blended therein either before or aftermilling. Examples of additional additives include fat-soluble colorcompounds, such as annatto and paprika extract and the like. Asmentioned above, moisture bearing substances (such as wheat flour andthe like) and thermally unstable substances (such as amorphous cornsolids and the like) may be included, but if used are preferably lessthan about 15 percent by weight of the filling. In a further preferredembodiment, such moisture bearing and thermally unstable substances aresubstantially absent from the filling. Optionally, low-water activity,edible inlays (such as roasted nuts, chocolate, candy, dry fruits, dryvegetables, herbs, spices, and the like) may be added to the fillerproduct after milling for flavor enhancement or cosmetic purposes aslong as they do not disrupt the microstructure and/or the bake stabilityof the filling.

By one approach, it is believed that suitable bake-stable, lipid-basedcreamy fillings have the general formulas as provided in Table 1 belowwhere, upon being milled, the crystalline-to-amorphous, solid-to-liquid,and/or sufficient quantities of high-melting lipid from the dust portionare combined to render the filling bake-stable.

TABLE 1 Formulas Ingredient Amount, % Low Melting Lipid(s) 30-70 HighMelting Lipid(s) 0.5-8   Dry Hydrophilic Powder(s) 30-70 OptionalIngredient(s)  0-10

Advantages and embodiments of the fillers described herein are furtherillustrated by the following Examples. However, the particularconditions, processing schemes, materials, and amounts thereof recitedin these Examples, as well as other conditions and details, should notbe construed to unduly limit this method. All percentages are by weightunless otherwise indicated.

Examples Comparative Example 1

A mixture of about 50 percent by weight cheese powder (SEQUOIA, KraftFoods Ingredients, Memphis, Tenn.) containing amorphous materials,particularly about 10 percent maltodextrin and about 31 percent spraydried lactose, were mixed with about 50 percent by weight soy bean oil.The mixture was mixed using a lab impeller mixer without milling. Uponheating of the mixture, agglomeration occurred at approximately 40° C.,resulting in oiling-out. At a temperature above 60° C., apparent lactosecrystallization occurs resulting in complete oil separation and aphysical change to a hard, sandy texture. As a result, thermallyunstable and hydroscopic ingredients, such as amorphous lactose andmaltodextrin, are believed to be detrimental to bake-stability.

Comparative Example 2

A mixture of 2 parts low lactose cheese powder (CHEEZTANG, Kraft FoodsIngredients, Memphis, Tenn.), 2 parts wheat flour, 1 part sugar, and 5parts filler fat (an edible shortening-like fat) were prepared withoutmilling by mixing the ingredients using a lab impeller mixture. Uponheating to about 50° C., agglomeration was observed, although oiling-outdid not occur until about 80° C. At a temperature of 80° C. or greater,the mixture becomes pasty and sticky. As a result, simply blendingingredients without milling does not result in a bake-stablecomposition.

Comparative Example 3

A mixture of Table 2 below was evaluated for bake-stability withoutmilling. First, an oil blend was prepared by mixing canola oil (CV 65Canola Oil, Cargill, Idaho Falls, Id.), melted Palm Oil (Sans Trans 39T15, Loders Croklaan, Channahon, Ill.), and Lecithin (Solec HR-2B, SolaeLLC, St. Louis, Mo.) together. A dry blend of calcium stearate (CASPSKNF FCC Kosher, American International Chemical, Natick, Mass.), non-fatdry milk powder (Grade A—Low Heat, Non-Fat Dried Milk, Dairy America,Fresno, Calif.), and crystalline lactose (Edible Lactose Fine Grind,Davisco Foods International, Inc., Eden Prairie, Minn.) were blendedtogether. Then, the dry blend was mixed together with the oil blendusing an impeller mixer without milling to form a uniform mixture.

TABLE 2 Mixture Ingredients Ingredients Amount, % Low-Melting LipidsCanola Oil 22.0 Palm Oil 27.4 Lecithin 0.5 High-Melting Lipid CalciumStearate 1.5 Hydrophilic Powders Crystalline Lactose 30.6 Non-Fat DryMilk 18.0 Milling No

For evaluating bake-stability, a small amount of a half-sphere roomtemperature sample was obtained using a small scoop (Cookie Scoop,Oneida Ltd, Oneida, N.Y.). The weight of this sample was about 14 to 16grams. The sample was then carefully placed at the center of a piece offilter paper (Whatman #1 Filter Paper, 15 cm, Whatman International Ltd,England) which is placed inside a Pyrex petri dish. This dish was thenheated in a pre-equilibrated oven at about 150° C. for about 10 minutes.After heating, the dish was removed from the oven and cooled on a benchtop for about 5 minutes. The increase in radius of filler andoil-bleeding from the edge of initial filler were measured incentimeters using a ruler.

The results of bake-stability test for this Comparative Example aresummarized in Table 3 below. This Comparative Example failed thebake-stability test and showed a significant amount of oil-bleeding andspread of filler after baking test. In addition, the baked sample alsoshowed significant browning.

TABLE 3 Results of Bake Stability Test Spread of Filler Oil-BleedingOverall Comparative 2.2 cm 5.2 cm Failed Example 3

Comparative Example 4

This Example used the same procedure and similar ingredients asComparative Example 3 except the filler contained only 0.1 percenthigh-melting calcium stearate and used milling conditions as provided inExample 1 below. The mixture is provided in Table 4 below. This samplealso failed the baking test with significant amount of oil-bleeding andspread of filler after heated in 150° C. oven for about 10 minutes. Inaddition, some degree of browning also occurred. Results are provided inTable 5 below.

TABLE 4 Formulation Ingredients Amount, % Low-Melting Lipids Canola Oil22.0 Palm Oil 27.4 Lecithin 0.5 High-Melting Lipid Calcium Stearate 0.1Hydrophilic Powders Crystalline Lactose 31.5 Non-Fat Dry Milk 18.0Milling Yes

TABLE 5 Results Spread of Filler Oil-Bleeding Overall Comparative 1.5 cm5.2 cm Failed Example 4

Example 1

The homogenous mixture from Comparative Example 3 was milled twice usinga Dyon-Mill (Dyno-Mill KDL Pilot, Glen Mills Inc., Maywood, N.J.) with agap setting at 0.5 mm to form a creamy mass with significant yieldstress. As shown in Table 6 below, after milling, the formulation ofComparative Example 3 showed very limited amount of oil-bleeding andspread of filler when compared to the results of the non-milledComparative Example 3. In addition, the filler maintained its color andshape as it was before the baking test. This demonstrated the importanceof micromilling and size reduction of particles in bake-stability.

TABLE 6 Results Spread of Filler Oil-Bleeding Overall Example 1 0.1 cm1.6 cm Pass

Example 2

A cheese-flavored creamy filler was prepared by first mixing ingredientsof Table 7 below with an impeller mixer and then milling the ingredientsto form a creamy mixture. First, an oil blend was prepared by mixingcanola oil (CV 65 Canola Oil, Cargill, Idaho Falls, Id.), melted PalmOil (Sans Trans 39 T15, Loders Croklaan, Channahon, Ill.), Lecithin(Solec HR-2B, Solae LLC, St. Louis, Mo.), and colors together. A drymixture of calcium stearate (CASPSK NF FCC Kosher, AmericanInternational Chemical, Natick, Mass.), cheese powder (CHEEZTANG, KraftFoods Ingredients, Memphis, Tenn.), crystalline lactose (Edible LactoseFine Grind, Davisco Foods International, Inc., Eden Prairie, Minn.),cream powder (cream powder TC, Kerry Ingredients, Beloit, Wis.), andminor dry flavor ingredients were blended together. Then, the drymixture was blended together with the oil blend using an impeller mixerto form a homogenous mixture. The homogenous mixture was then milledtwice using a Dyon-Mill (Dyno-Mill KDL Pilot, Glen Mills Inc., Maywood,N.J.) with a gap setting of 0.5 mm to form a creamy mass withsignificant yield stress. A particle size analysis of the filler wascompleted using a Horiba particle size analyzer. A graph of the particlesize distribution is provided in FIG. 3.

TABLE 7 Formulation Ingredients Amount, % Low-Melting Lipids Canola Oil30.0 Palm Oil 9.0 Lecithin 0.3 High-Melting Lipid Calcium Stearate 5.0Hydrophilic Powders Crystalline Lactose 30.8 Cream Powder 3.0 CheesePowder 18.0 Optional Ingredients Flavor Ingredients 3.9 ColorIngredients 0.04 Milling Yes

As shown in the Table 8, the bake-stable cheese filler of this Exampleshowed only a minimum amount of spread and oil bleeding when tested withoven baking test procedure as described in Comparative Example 3.

TABLE 8 Results Spread of Filler Oil-Bleeding Overall Example 4 0.1 cm1.5 cm Pass

Example 3

This Example evaluates a creamy, pizza-flavored bake-stable filler. Thedetailed formulation is shown below in Table 9. Similar to ComparativeExample 3, an oil-blend was prepared by mixing canola oil (CV 65 CanolaOil, Cargill, Idaho Falls, Id.), melted Palm Oil (Sans Trans 39 T15,Loders Croklaan, Channahon, Ill.), Lecithin (Solec HR-2B, Solae LLC, St.Louis, Mo.), and colors together. A dry mixture of calcium stearate(CASPSK NF FCC Kosher, American International Chemical, Natick, Mass.),tomato powder (Tomato Powder Stand Grind, Agusa, Lemoore, Calif.),crystalline lactose (Edible Lactose Fine Grind, Davisco FoodsInternational, Inc., Eden Prairie, Minn.), and minor dry flavoringredients were blended together. Then, the dry mixture was blendedtogether with the oil-blend using an impeller mixer to form a homogenousmixture. The homogenous mixture was then milled twice using a Dyon-Mill(Dyno-Mill KDL Pilot, Glen Mills Inc., Maywood, N.J.) with a gap settingof 0.5 mm to form a creamy mass with significant yield stress. Aftermilling, a dry blend of spice and herb was then mixed with the milledsample to form the finished filler.

TABLE 9 Formulation Ingredients Amount, % Low-Melting Lipids Canola Oil28.0 Palm Oil 27.0 Lecithin 0.3 High-Melting Lipid Calcium Stearate 8.0Hydrophilic Powders Crystalline Lactose 19.2 Tomato Powder 12.0 OptionalIngredients Flavor Ingredients 3.5 Herb and Spices 2.0 Color Ingredients0.04 Millling Yes

As shown in Table 10, the bake-stable pizza flavored filler of thisExample showed only a minimum amount of spread and oil-bleeding whentested with oven baking test procedure as described in ComparativeExample 3.

TABLE 10 Results Spread of Filler Oil-Bleeding Overall Example 4 0.1 cm1.8 cm Pass

Example 4

This experiment was completed to demonstrate that a sub-micron fractionof calcium stearate particles was generated as a result of milling underidentical milling conditions used for Examples 1-3. About 25 weightpercent of calcium stearate in a low-melting lipid (Neobee oil, a mediumchain triglyceride from Stepan Company, Northfield, Ill.) was milledusing a Dyno-mill (Dyno-Mill KDL Pilot, Glen Mills Inc., Maywood, N.J.)with a gap setting of 0.5 mm to form a creamy mass.

Four grams of milled material was dispersed in about 37 grams of acetoneto make up about a 50 ml thoroughly dispersed suspension in a glassgraduate cylinder. The suspension was allowed to settle at roomtemperature for about 15 hours. The undisturbed, settled suspension wassiphoned out carefully with a pipet into about 5 equal fractions about10 ml each in volume from the top to the bottom of the settledsuspension. Each fraction was placed in small, reweighed glass vial witha screw cap for tight seal. Evaporation of acetone was minimized duringthe fractionation process. A control was also prepared with unmilledcalcium stearate/Neobee oil mixture (obtained before milling) inidentical fashion. The weight of each fractions was recorded prior toand after the complete removal of acetone by evaporating at about 55° C.in a ventilated hood. The weight percents of calcium stearate in eachfraction were shown and compared to those of the control in the FIG. 4.

The results suggest that a sub-micron fraction (i.e., mainly fraction #1at the top of the settled suspension and possibly fraction #2) wasgenerated by milling. This fraction represents at least about 5 to about10 percent of the total calcium stearate. This sub-micron fraction issubstantially absent in the (unmilled) control. It is believed that thissub-micron fraction of calcium stearate is effective for preventinghydrophilic particles (e.g., cheese, lactose) from aggregation atmilling and baking temperature. It is further believed that thesub-micron fraction of calcium stearate is also at least partiallyresponsible for the reduction of oil bleeding.

FIG. 5 shows a SEM (Scanning Electron Microscope) image of the milledcalcium stearate from the top fraction number 1 of FIG. 4. FIG. 5indicates the existence of numerous and mainly sub-micron-sized calciumstearate upon the sample being milled. The relative scale of 1 micron isshown in the legend on the lower right of the image. Thus, fraction 1 isbelieved to include mainly sub-micron sized particles of calciumstearate. In these images, the particles tend to stick together in oilas acetone is being removed or evaporated per the test procedure.

It will be understood that various changes in the details, materials,and arrangements of the process, formulations, and ingredients thereof,which have been herein described and illustrated in order to explain thenature of the method and resulting lipid-based fillers, may be made bythose skilled in the art within the principle and scope of the embodiedmethod as expressed in the appended claims.

1. A method of forming a lipid-based, creamy food filling that isbake-stable up to a temperature of at least about 125° C., the methodcomprising: blending a hydrophilic powder, a high-melting lipid with amelting point of at least about 70° C., and a low-melting lipid having amelting point of about 40° C. or below to form a blended mixture;milling the blended mixture to form a particle size distribution of thehigh-melting lipid and the hydrophilic powder; and the particle sizedistribution includes an amount of the high melting lipid with aparticle size of about 4 microns or less to render the creamy foodfilling bake-stable so that it exhibits substantially no spreading ofthe filling and substantially no oil-bleeding of the filling upon asample of the creamy food filling heated for about 10 minutes at about150° C.
 2. The method of claim 1, wherein the blended mixture includesabout 30 to about 70 percent of the hydrophilic powder, about 0.5 toabout 8 percent of the high-melting lipid, and about 30 to about 70percent of the low-melting lipid.
 3. The method of claim 1, wherein theparticle size distribution includes at least about 90 percent of theparticles less than about 30 microns and at least about 10 percent ofthe particles less than about 4 microns.
 4. The method of claim 1,wherein the particle size distribution is a bi-modal particle sizedistribution including a dust particle portion having a sub-distributionof dust particles less than about 4 microns with an amount of sub-microndust particles less than about 1 micron effective to render the fillingbake stable and a creamy particle portion having a sub-distribution ofcreamy particles greater than about 4 microns.
 5. The method of claim 1,wherein the particle size distribution is a bi-modal particle sizedistribution of the high-melting lipid and the hydrophilic powderincluding one mode of a dust particle portion having a sub-distributionof dust particles less than about 4 microns and another mode including acreamy particle portion having a sub-distribution of creamy particlesgreater than about 4 microns.
 6. The method of claim 5, wherein, theblended mixture includes between about 30 and about 70 percent by weightof the hydrophilic powder, about 0.5 to about 8 percent by weight of thehigh-melting lipid, and between about 30 and about 70 percent by weightof the low-melting lipid.
 7. The method of claim 5, wherein the particlesize distribution includes at least about 90 percent by volume of theparticles less than about 30 microns and at least about 10 percent byvolume of the particles less than about 4 microns.
 8. The method ofclaim 5, wherein the dust particle portion includes sub-micron dustparticles of less than about 1 micron.